Download or read book Welding and Joining of Advanced High Strength Steels AHSS written by Mahadev Shome and published by Elsevier. This book was released on 2015-02-25 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: Welding and Joining of Advanced High Strength Steels (AHSS): The Automotive Industry discusses the ways advanced high strength steels (AHSS) are key to weight reduction in sectors such as automotive engineering. It includes a discussion on how welding can alter the microstructure in the heat affected zone, producing either excessive hardening or softening, and how these local changes create potential weaknesses that can lead to failure. This text reviews the range of welding and other joining technologies for AHSS and how they can be best used to maximize the potential of AHSS. - Reviews the properties and manufacturing techniques of advanced high strength steels (AHSS) - Examines welding processes, performance, and fatigue in AHSS - Focuses on AHSS welding and joining within the automotive industry

Download or read book Resistance Spot Welding of Advanced High Strength Steels written by and published by . This book was released on 2019 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Resistance Spot Welding written by Menachem Kimchi and published by Springer Nature. This book was released on 2023-04-23 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book begins with thorough coverage of Resistance Spot Welding fundamentals and principles, including concepts such as Lobe Curves, contact resistance vs. electrode force, dynamic resistance, heat balance challenges, nugget growth, machine types and power supplies, and electrodes. Subsequent chapters address challenges and approaches to important topics of welding advanced high-strength steels, such as DP, TRIP, TWIP, and Press Hardening Steel, as well as aluminum alloys. Welding issues associated with the various coatings used on these steels are addressed. The final chapters are dedicated to weld quality, monitoring, testing, computational modeling, and common automotive production issues such as the welding of multiple sheet stack-ups and a brief overview of associated codes and standards. The second edition includes updated chapters and additional information, such as expanded information on welding aluminum to steel, a new section on alternative welding and joining methods, and updates on monitoring and control as well as welding issues associated with the latest advanced high-strength steels.

Download or read book Spot Welding of Advanced High Strength Steels AHSS written by Mohammad Ibraheem Khan and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Joining of Advanced High Strength Steels Using Resistance Spot Welding written by Christopher Carl Edward Miller and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Resistance Spot Welding written by Menachem Kimchi and published by Springer Nature. This book was released on 2022-05-31 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: The early chapters of this book provide thorough coverage of resistance spot welding fundamentals and principles. Topics covered include lobe and current range curves, contact resistance vs. electrode force, dynamic resistance, heat balance, nugget growth, etc. Equipment issues such as machine types, power supplies, and electrodes are addressed. Subsequent chapters focus on specific spot welding challenges to modern automotive manufacturing. Approaches to welding modern materials including advanced high-strength steels, coated steels, and aluminum alloys are covered in much detail. The final chapters focus on many common production and quality control issues, such as electrode wear, monitoring and testing, computational modeling, and welding codes. The overall goal of the book is to provide a comprehensive resource for automotive engineers and technicians who work with modern spot welding equipment and automotive materials.

Download or read book Effect of Surface Condition on Resistance Spot Welding of Advanced High Strength Steel written by Xu Han and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced high strength automotive sheet steel (AHSS) is used in body-in-white design to reduce vehicle weight while maintaining high crashworthiness. Surface coatings applied to AHSS to protect it from oxidation and decarburization during its processing and life cycle. Due to the characteristics of AHSS, including alloying content and thermal process requirements, a variation of final surface conditions is possible. The resistance welding process is affected by surface changes as it alters the electrical contact resistance. As a result, a change in resistance spot welding process window occurs. Without proper attention, this variation in the operation window could reduce the joint strength and results in an unpredictable failure by having an undersized nugget. In this study, two surface-related phenomena, internal oxidation, and zinc diffusion, were investigated to characterize their impact on resistance spot welding. Additionally, a heat input based electrical dynamic resistance approach was proposed to determine appropriate welding current given variations in the Zn diffusion layer resulting from heat treating during this hot stamping process for PHS steels. Promotion of internal oxidation is used in Zn galvanizing line to improve the wettability of the steel surface to the Zn pool via the enhancement of the reactive wetting. The presence of these internal oxides has shown to shift the weld lobe to higher currents, increasing the time required to generate an acceptable weld. Study of weld development showed that surface melting is responsible for this shift in the weld process window. The surface melting created a liquid contact surface between the faying surface, which reduced the electric contact resistance and heat generation at the weld faying surface. A smaller nugget was formed due to the reduction of heating. To compensate for this reduced heat generation, a higher welding current was required when RSW of internally oxidized samples. Zinc diffusion from the galvannealed coating to the steel substrate occurs when a galvannealed steel was exposed to elevated temperature during heat treatment in the press-hardening process. This formed a Fe-Zn diffusion layer. The thickness and composition of the diffusion layer were found to be dependent on heat-treatment conditions. With an increase in heat-treatment time, the electrical resistance of the steel sheet was observed to increase as well. With higher electrical resistance, less welding current was needed to weld the material. While a change in nugget size occurred when welding steels made using different heat-treatment conditions with constant welding parameters, the mechanical lap shear strength was not impacted. Martensite tempering in the heat-affected region was more severe in samples with a larger diameter weld nugget, which decreased the required stress for failure to occur, counter-acting the increase in strength gained from the larger nugget size. This work has shown that with a heat-treatment time ranging between 4 to 10 minutes, a robust resistance welding schedule can be determined to generate a mechanically sound weld. Dynamic electrical resistance has been used to monitor the weld quality. Heat input analysis was shown to reflect the weld development as it takes into account the full weld cycle. Heat input has shown to have a linear correlation with nugget size. Undersized nugget can be successfully detected and corrected by changing the welding current based on the heat input value calculated from dynamic resistance measurement.

Download or read book Resistance Welding written by Hongyan Zhang and published by CRC Press. This book was released on 2011-12-13 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drawing on state-of-the-art research results, Resistance Welding: Fundamentals and Applications, Second Edition systematically presents fundamental aspects of important processes in resistance welding and discusses their implications on real-world welding applications. This updated edition describes progress made in resistance welding research and

Download or read book Liquid Metal Embrittlement of Advanced High Strength Steels During Resistance Spot Welding written by Julian Frei and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Steels written by Yuqing Weng and published by Springer Science & Business Media. This book was released on 2011-04-14 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Advanced Steels: The Recent Scenario in Steel Science and Technology" contains more than 50 articles selected from the proceedings of the International Conference on Advanced Steels (ICAS) held during 9-11, Nov, 2010 in Guilin, China. This book covers almost all important aspects of steels from physical metallurgy, steel grades, processing and fabrication, simulation, to properties and applications. The book is intended for researchers and postgraduate students in the field of steels, metallurgy and materials science. Prof. Yuqing Weng is an academician of Chinese Academy of Engineering and the president of The Chinese Society for Metals. Prof. Han Dong is the vice president of Central Iron & Steel Research Institute and the director of National Engineering Research Center of Advanced Steel Technology, China. Prof. Yong Gan is an academician of Chinese Academy of Engineering, the vice president of Chinese Academy of Engineering and the president of Central Iron & Steel Research Institute, China.

Download or read book Advanced High Strength Steels written by Mahmoud Y. Demeri and published by ASM International. This book was released on 2013-08-01 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines the types, microstructures and attributes of AHSSAlso reviews the current and future applications, the benefits, trends and environmental and sustainability issues.

Download or read book Resistance Spot Welding of Low Carbon and High Strength Steels written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book HSLA Steels 2015 Microalloying 2015 Offshore Engineering Steels 2015 written by The Chinese Society for Metals and published by Springer. This book was released on 2017-03-22 with total page 1147 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a collection of papers presented at the joint conference of the 7th International Conference on High Strength Low Alloy Steels (HSLA Steels 2015), the International Conference on Microalloying 2015 (Microalloying 2015), and the International Conference on Offshore Engineering Steels 2015 (OES 2015). The papers focus on the exchange of the latest scientific and technological progresses on HSLA steels, microalloying steels, and offshore engineering steels over the past decades. The contributions are intended to strengthen cooperation between universities and research institutes, and iron and steel companies and users, and promote the further development in the fields all over the world.

Download or read book Towards Understanding the Effects of Current Input on Fatigue Mechanisms in Resistance Spot Welding of Advanced High Strength Steels written by Conner Cleek and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, the relationship of welding parameters to fatigue mechanisms is examined in spot welding of advanced high strength steels. Lightweighting efforts in the automotive industry are part of a push for greater fuel economy and improved consumer safety. TBF-1180 is an advanced high strength steel being developed for use in structurally critical components, however its fatigue behavior is not well understood. Electro galvanized TBF-1180 possesses corrosion resistant properties, however the additional zinc layer allows for the possibility of zinc-penetrative liquid metal embrittlement (LME) to occur during resistance spot welding (RSW). Additionally, variations in weld input and correspondingly heat input can affect the performance of welds due to microstructural changes that occur. In this study, the effect of LME and changes in microstructure were assessed in separate experiments for their fatigue impact in TBF-1180. Welds were fabricated in a traditional lap shear geometry in order to investigate the effects of LME, while an hourglass shaped cap geometry was used for welds with microstructural variation. Fatigue testing revealed that for lap-shear coupons containing LME cracks, no deleterious effect was observed. Cap geometry specimens were assessed for performance in a control and a high-current low-time condition, and a significant fatigue knockdown factor was found. Post-mortem fractography on both specimen geometries revealed that fatigue cracks initiated at the inner faying surface, regardless of the presence of LME. Finite element analysis confirmed that the LME cracks in the lap shear weld experience compressive stresses during loading, contributing to the lack of fatigue impact. Experimental conditions used for the cap geometry had lower heat input, which can result in less retained metastable austenite after welding, leading to reduced crack growth resistance. To tests the hypothesis that less retained metastable austenite after welding can cause a reduction in the number of cycles to failure in the spot weld, life prediction were made using fracture mechanics concepts coupled with reported knockdown factors on crack growth rates in relation to the amount of transformed martensite. The life predictions generated with this method strongly matched the observed fatigue behavior for the cap geometry specimens.

Download or read book Friction Stir Spot Welding of Advanced High Strength Steels written by Jeffrey M. Rodelas and published by . This book was released on 2008 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The application of friction stir spot welding (FSSW) for joining advanced high strength steel (AHSS) offers improvements in automobile fuel economy and crashworthiness. FSSW is a solid-state process and therefore bypasses liquid phases that form during conventional resistance spot welding. This process eliminates detrimental solidification weld defects such as cracking and debonding. A hybrid hi-material FSSW tool comprised of cobalt-cemented tungsten carbide (WC-Co) was bonded to a tungsten-nickel-iron heavy alloy (WHA). A unique sinterbonding process was used to bond the two materials. Sinterbonding WC-Co powder to WHA, using hot pressing to apply pressure, resulted in an ideal consolidated interface. Thermodynamic analyses showed cobalt-rich eta-phase carbides are favored to form at the interface due to a reduction in carbon activity. The mechanical performance of FSSW welds on various AHSS was evaluated. For constant FSSW parameters, martensitic AHSS (M190) did not result in higher lap shear strengths (LSS) compared to dual phase AHSS (DP 590) which has less than half the tensile strength M190. The results suggest that higher strength materials are more resistant to material flow under the tool during welding, which results in smaller bonded regions and LSS. The formation of a strength-reducing soft ferrite layer originating from the sheet faying surfaces was investigated for a martensitic AHSS. A series of welds with varying process times (i.e., varying total energy input) was performed to investigate welding parameter effects on the ferritic layer formation. For the conditions explored, the extent of ferrite formation was dependent on oxygen availability"--Abstract, leaf iv.

Download or read book Resistance Spot Welding of Advanced High Strenght Steels written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Properties of Resistance Spot Welds in High Strength Steels written by Neil Stevenson and published by . This book was released on 1984 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: